The body of 21-year-old Joseph Witherington, of Lakeland, was found in the driver's seat of a blue Kia. He had been shot in the head twice, according to the Polk County Sheriff's Office.

The sheriff's office says he was killed and left there by 28-year-old Heather Tyler.

Authorities say tips led them to Tyler, who told them the victim picked her up Wednesday night. They drove out to the orange grove on 80 Foot Road after hanging out for several hours, the sheriff's office says.

Tyler then told several different versions of what happened inside the vehicle after that, according to the sheriff's office.

The sheriff's office says witness statements and evidence confirm that Tyler shot the victim. They say she shot him once while he was driving, then again after the vehicle came to a stop. She then stole his wallet and ran from the scene.

After running, Tyler burned the clothes she was wearing, according to the sheriff's office.

Detectives say she did not give a clear motive for the murder.

Tyler was arrested Friday night for first degree murder, tampering with evidence and grand theft of a fire arm.

"Regardless of Heather's many reasons and excuses, we know that she executed Joseph Witherington by shooting him in the back of the head while he was driving down a dirt road between orange groves - and that is first degree murder and we have charged her accordingly," Sheriff Grady Judd said. "Clearly the evidence, witnesses, and her admissions confirm that she committed cold blooded first degree murder. Joseph's family and friends are in our prayers. If not for the vicious act by Heather Tyler, he would be alive and well today."

"We've arrested 28-yr-old Heather Tyler of #Lakeland for the cold-blooded first degree murder of 21-yr-old Joseph Witherington. He would be alive today if not for her viciousness. His family & friends are in our prayers." - Sheriff Judd. Read the release: https://t.co/s0dDxduF7Npic.twitter.com/lgxGghourM